1. Field of the Invention
The present invention relates to a system for calibrating a sound field when receiving a stereophonic broadcasting, and especially to apparatuses that enable the maintenance of a stereophonic broadcasting in spite of an interruption.
2. Description of the Related Art
In recent years, a system for calibrating a sound field to improve presence has been widely used, because digital audio technology processing sound signals digitally has expanded.
It is well-known that this system processes a monophonic signal that is produced by adding an L-channel signal and an R-channel signal, or subtracting an L-channel signal from an R-channel signal.
Presence will be increased by the system that calibrates a sound field using a monophonic signal especially when an orchestra or a big band with vocals is reproduced because the sound to be localized at the center can be clearly maintained.
In the case that the above sound field calibrator is applied to a car audio system, however, listeners experience that presence is suddenly changed when a vehicle passes through an area that has a weak electric field, because the stereophonic tuner outputs same (R+L) monophonic signal from an R-channel output terminal and an L-channel output terminal in that area, and the output signal of the mixing amplifying part is cancelled.